Cushioning materials may comprise gelatinous elastomers and lightweight fillers. Gelatinous elastomers may comprise an elastomeric polymer, such as an A-B-A triblock copolymer elastomer, and a plasticizer. The plasticizer may be mineral oil or another hydrocarbon fluid.
Gelatinous elastomers having A-B-A tri-block copolymers are described, for example, in U.S. Pat. No. 6,797,765, issued Sep. 28, 2004 to Pearce, and U.S. Pat. No. 5,994,450, issued Nov. 30, 1999 to Pearce, which are each incorporated herein in their entirety by this reference. Gelatinous elastomers have a variety of uses. U.S. Pat. No. 6,026,527, issued Feb. 22, 2000 to Pearce, and U.S. Pat. No. 5,749,111, issued May 12, 1998 to Pearce, which are each incorporated herein in their entirety by this reference, describe cushioning elements including gelatinous elastomers. Such gelatinous elastomers are commercially available from EdiZONE, LLC of Alpine, Utah.
Conformable cushions may be formed from cushioning materials disclosed in U.S. Pat. No. 5,421,874, issued Jun. 6, 1995 to Pearce, U.S. Pat. No. 5,549,743, issued Aug. 27, 1996 to Pearce, U.S. Pat. No. 5,626,657, issued May 6, 1997 to Pearce, and U.S. Pat. No. 6,020,055, issued Feb. 1, 2000 to Pearce, each of which is fully incorporated herein by this reference. Cushioning materials are commercially available from EdiZONE, LLC of Alpine, Utah, under the trade names FLOAM™ and Z-FLO™.
FIG. 1 illustrates a cushion 10 including a bladder 12 in which a self-forming fluid cushioning material 14 known in the art and commercially available under the trade name FLOAM™ is disposed. The cushioning material 14 comprises a mixture of liquid and microspheres. The liquid comprises an oil plasticizer (about 99.25% by weight of the liquid) and a relatively small amount of an elastomeric polymer material (about 0.75% by weight of the liquid) dissolved within the oil plasticizer. The cushioning material 14 has a density of about 0.33 g/cm3. The cushion 10 may be disposed within a base 15. The liquid in FLOAM™ generally has a plasticizer-to-polymer ratio by weight of greater than about 100-to-1, such as about 133-to-1.
An object or body part 16 placed upon the cushion 10 is supported along surfaces of the object or body part 16 in contact with the cushion 10. The object or body part 16 may be supported by the cushion 10 via pressures 17 and 18 (indicated by arrows in FIG. 1) over areas in which the object or body part 16 contacts the cushion 10. In areas in which the object 16 does not contact the cushion 10, the cushion 10 does not support the object or body part 16. For example, spaces or gaps 19 between the object or body part 16 and the cushion 10 result in areas of the object or body part 16 unsupported by the cushion 10. The magnitude of the pressures 17 and 18 needed to support the object 16 varies inversely with the area over which the pressures 17 and 18 apply.